Shutter press compressor with movable jaws

ABSTRACT

An apparatus for compressing a material includes a central longitudinal axis, a plurality of levers each having a tool carrier and defining a lever longitudinal axis, and a plurality of jaws each attached to a lever at a tool carrier to form a lever/jaw combination, wherein each jaw has a compression surface having an area. The apparatus also includes a compressing mechanism configured to move each lever in a non-linear motion such that the area of a compression surface exposed to the material decreases with the inward movement of that compression surface, wherein each lever/jaw combination includes a biasing mechanism configured such that adjacent jaws contact each other. The plane of each compression surface can be predominantly tangential to the apparatus central longitudinal axis. Each biasing mechanism can be configured to bias its jaw along the lever longitudinal axis toward an adjacent jaw.

BACKGROUND

Radial presses are currently used to compress materials for reasons including the addition of stability, the reduction of volume, and the addition of shape to the material. An uncompressed sample of material is inserted into a press, and jaws are moved inwardly in a radial direction to compress the material. Spaces between jaws are required to allow the jaws to move inwardly over a limited range without interfering with neighboring jaws. Because of this design, however, material can migrate into the spaces between the radius jaws of prior presses during compression. This can cause the material or product to become aesthetically unacceptable, limited in expected performance, or even dangerous. In addition, portions of the material or product can become bent, pinched, torn, deformed, or raised during manufacture of the product.

In a specific example, tampons are initially formed in a non-compressed state using various absorbent materials in a flat configuration. To make a tampon pledget that is of a suitable shape and integrity for insertion, the uncompressed absorbent materials must be folded, rolled, or stacked in such a manner to allow the uncompressed absorbent materials or blank to be inserted into a tampon compression apparatus or press. This press reduces the volume of the absorbent material until sufficient compression occurs and the blank is temporarily deformed into a tampon pledget that can be inserted into the vaginal cavity to absorb various body fluids including menses. In addition, modern tampon designs can include a secondary absorbent structure such as petals that are designed to migrate in a radial direction from the tampon pledget. Such petals can become bent, pinched, torn, deformed, or raised during manufacture of the product. Further, insufficient compression can prevent a used tampon from remaining fully intact as it is withdrawn; the tampon can substantially delaminate, unroll, unfold, telescope, or otherwise structurally degrade.

To combat these structural issues, numerous attempts to stabilize compressed material have been undertaken. For example, some have tried binder fibers, adhesives, grooved compression, needling, microwave radiation, and the like. However, despite these efforts, there still exists a need for compressed materials to have greater stability during storage and use.

SUMMARY

In one aspect, the present disclosure provides an apparatus for compressing a material, the apparatus including a plurality of levers each having a tool carrier and a plurality of jaws each attached to a lever at a tool carrier to form a lever/jaw combination, wherein each jaw has a compression surface having an area. The apparatus also includes a compressing mechanism configured to move each lever in a non-linear motion such that the area of a compression surface exposed to the material decreases with the inward movement of that compression surface, wherein each lever/jaw combination includes a biasing mechanism configured such that adjacent jaws contact each other.

In another aspect, the present disclosure provides an apparatus for compressing a material, the apparatus having a central longitudinal axis and including a plurality of levers each having a tool carrier and a plurality of jaws each attached to a lever at a tool carrier to form a lever/jaw combination, wherein each jaw has a compression surface having an area and defining a plane. The apparatus also includes a compressing mechanism configured to move each lever in a non-linear motion such that the area of a compression surface exposed to the material decreases with the inward movement of that compression surface, wherein each lever/jaw combination includes a biasing mechanism configured such that adjacent jaws contact each other, and wherein the plane of each compression surface is predominantly tangential to the apparatus central longitudinal axis.

In another aspect, the present disclosure provides an apparatus for compressing a material, the apparatus including a plurality of levers each having a tool carrier and defining a lever longitudinal axis and a plurality of jaws each attached to a lever at a tool carrier to form a lever/jaw combination, wherein each jaw has a compression surface having an area. The apparatus also includes a compressing mechanism configured to move each lever in a non-linear motion such that the area of a compression surface exposed to the material decreases with the inward movement of that compression surface, wherein each lever/jaw combination includes a biasing mechanism configured to bias its jaw along the lever longitudinal axis toward an adjacent jaw.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features and aspects of the present disclosure and the manner of attaining them will become more apparent, and the disclosure itself will be better understood by reference to the following description, appended claims and accompanying drawings, where:

FIG. 1 representatively illustrates an exemplary tampon of the present disclosure.

FIG. 2 representatively illustrates an exemplary apparatus used in making the tampon of FIG. 1, in an open position.

FIG. 3 representatively illustrates an exemplary apparatus used in making the tampon of FIG. 1, in a minimum compression position.

FIG. 4 representatively illustrates a lever used in the apparatus of FIGS. 2 and 3.

FIG. 5 representatively illustrates a jaw used in the apparatus of FIGS. 2 and 3.

Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present disclosure. The drawings are representational and are not necessarily drawn to scale. Certain proportions thereof might be exaggerated, while others might be minimized.

DETAILED DESCRIPTION

Prior presses have a multiplicity of compression members commonly called jaws that contact the outer surface of the uncompressed material and simultaneously reduce the material diameter until sufficient densification of the fibers occurs such that the pressure created temporarily deforms the materials into a stable, pressed condition.

Prior presses with multiple compression jaws operate in a motion that is generally in a linear, radial direction (in and out) from the theoretical center of the press. As such, the multiple independent jaws have spaces between adjacent jaws where the materials near the surface of the uncompressed material will become deformed during the compression process. Portions of the uncompressed material can migrate around the compression surface of the jaw and into the spaces between adjacent jaws thus becoming caught between the jaws at minimum compression. Such deformation can intentionally or unintentionally create undulations or wrinkles to accommodate the reduction of diameter during the compression process. In some applications this is a desirable effect to create more uniform densities or to enhance the surface area of a product. In other applications, such as those described herein, the deformation can cause wrinkles or a line of weakness such that at least a portion of a product is damaged or substantially compromised in strength. The uncompressed material can have the additional propensity to undesirably migrate into the spaces between jaws.

A specific but non-limiting example of the use of the press of the present disclosure is in the manufacture of tampons. The tampon of the present disclosure is designed to be inserted above the introital region of a woman's vagina and is designed to function so as to intercept the fluid flow of menses, blood, and other body fluids and prevent the fluid from exiting the vagina. While the pledgets of the present disclosure are described for use as a menstrual device, it will be readily apparent that the pledgets can also be used as any other suitable vaginal insert, such as a pessary. Likewise, while the pledgets of the present disclosure are generally described as being absorbent, it will be readily apparent that the pledgets can be coated or otherwise treated to be partially or completely non-absorbent.

Improvement to the effectiveness of a tampon product can be made by adding a secondary absorbent layer to the absorbent structure of the tampon. The secondary layer has individual contact members that can increase the mucosal contact region with the vaginal wall beyond the diameter of the standard radially-wound tampon. Although this feature is advantageous for its ability to contact and absorb vaginal fluids over a larger surface area, the contact member or petal can become bent, twisted, or torn during the tampon-making process, resulting in the petal not lying flat to the outer surface of the tampon soft roll/uncompressed blank and/or to the compressed tampon pledget during the compression process.

It should be noted that the press device described herein is described using tampon compression as an example, but is equally suitable for use in compressing any compressible material including raw materials and products, and particularly any generally uncompressed material that can be made into a compressed cylindrical material.

As is shown in FIG. 1, exemplary tampons 10 include a mass of fibrous material 11 compressed into a generally cylindrically-shaped pledget 20. The tampon 10 generally has an insertion end 38 and an opposite withdrawal end 42. The insertion end 38 is designed to be the first part of the tampon that enters the woman's vaginal cavity. In some aspects, the insertion end 38 can be rounded or otherwise shaped to facilitate insertion. While in use, the pledget 20 of the present disclosure is designed to be positioned entirely within the woman's vagina. The tampon 10 can also include contact elements (not shown) such as those described in co-pending U.S. patent application Ser. Nos. 13/333,150, 13/333,311, 13/537,138, and 13/537,153, which are incorporated herein to the extent they do not conflict herewith.

The tampon 10 further includes a withdrawal string 21 for assisting in removing the tampon 10 from the woman's vagina. The withdrawal string 21 can be attached to the pledget 20 in any suitable manner. The withdrawal string 21 can further include one or more knots 31 to prevent fraying of the withdrawal string 21 and to provide a point where a woman can grasp the withdrawal string 21 when she is ready to remove the tampon 10 from her vagina.

When the woman pulls on the withdrawal string 21, forces are applied to the connection points between the withdrawal string 21 and the pledget 20. These forces are counteracted by the frictional forces between the pledget 20 and the vaginal walls. The frictional forces vary depending upon the saturation level of the pledget, the presence and/or type of cover material, pledget expansion, pledget orientation, the rheology of the body fluids present, and numerous other factors. Regardless of the various factors, it is desirable that the integrity of the pledget 20 be such that it can withstand the countervailing forces without delaminating, unrolling, unfolding, telescoping, or otherwise structurally degrading. While not wishing to be bound by theory, it is believed that these and other structural degradations are caused, at least in part, by shifting between various layers or structures of the pledget 20. These shifts are believed to be compounded by the fact that the pledgets 20 are generally made from ribbons of fiber that can be wound, folded, stacked, gathered, bunched, waded, bagged, or the like. Past efforts to stabilize the pledget 20 have included the use of binder fibers, adhesives, grooved compression, needling, microwave radiation, and the like in an effort to achieve fiber-to-fiber stability. While these methods have had mixed success, the present disclosure is believed to increase layer or structure integration by mechanically driving uniform compression and limiting pinch points.

The apparatus described herein is designed to radially compress a material, including the specific example of manufacturing a tampon 10. The apparatus has compressing surfaces and a compressing mechanism to move the compressing surfaces in a nonlinear motion while compressing the material. As the apparatus compresses, the compressing surface area decreases and circumferential gapping is maintained close to zero over the relevant range of the apparatus. The operating range of the apparatus is defined as the range between the maximum compression diameter and the minimum compression diameter. The ratio of the initial compression diameter to the final compression diameter, or the compression ratio, obtainable with this apparatus is one or greater in one aspect, greater than two in another aspect, and greater than three, four, five, six, seven, eight, nine, ten, 15, 20, or more in other aspects. The initial compression diameter is the effective diameter of the material prior to compression, which is essentially the minimum diameter to which the apparatus must be opened to accept the material. The diameter in the preceding terms is the diameter of the hypothetical cylinder 110 defined below. The final compression diameter is the desired diameter of the material after compression.

By maintaining circumferential gapping close to zero over the relevant range of the apparatus, the compression jaws can reinforce each other to improve apparatus stability.

A press device 50 for manufacturing the tampon 10 described herein is illustrated in FIG. 2. The press device 50 used as an example here includes eight levers 54 (see FIGS. 2-4), although any suitable number of levers 54 can be accommodated. The center of the press device 50 defines a central longitudinal axis 58, which is the point at which the jaws 94 meet when the levers 54 and jaws 94 are at their innermost extent of travel. Each lever 54 is connected to a fixed ring 62 with a pivot pin 66 and is pivotable within certain limits about the pivot pin 66. Each lever 54 has a lever outer end 70 that is pivotably linked by first and second coupling pins 74, 78 to adjacent chain links 82 as a part of a drive mechanism (not shown). The first and second coupling pins 74, 78 and the pivot pins 66 can each be positioned in generally circular array, or in any other suitable array. The spacing between adjacent coupling pins 74, 78 and between adjacent pivot pins 66 is determined by the number of levers 54 to be included within the circle.

The levers 54 are designed as angle levers and each includes a lever arm 86 that is positioned radially inwardly. Each lever 54 has a lever longitudinal axis 88 extending from the lever outer end 70 through the pivot pin 66 to a radially-inward end portion 90 of each lever arm 86. The radially-inward end portion 90 includes a jaw 94 used in compression. The jaw 94 can be formed integrally with the lever arm 86 and therefore be a portion of the lever 54 itself, the jaw 94 can be attached to the lever arm 86 at a tool carrier 98 on the radially-inward end portion 90 of the lever arm 86, or the jaw 94 can be associated with the lever 54 in any suitable manner. In various aspects of the present disclosure, the number of levers and jaws can be 3, 4, 5, 6, 8, 10, 12, 16, or any other suitable number.

Each jaw 94 includes a compression surface 102 and a jaw edge 106 (see FIG. 5). The compression surface 102 defines a plane that is generally parallel to the lever longitudinal axis 88. In the illustrated aspect, each jaw 94 projects toward an adjacent jaw 94 where the adjacent jaw 94 is positioned in a clockwise direction from the first jaw 94. The jaw edge 106 of one jaw 94 is disposed in the vicinity of the compression surface 102 of the clockwise-adjacent jaw 94. The topography of a given jaw edge 106 essentially matches the topography of the compression surface 102 of an adjacent jaw 94. The press device 50 is arranged such that a plane defined by the compression surface 102 of each jaw 94 is at all points in the compression cycle tangential to the central longitudinal axis 58.

In addition, each compression surface 102 defines an area that is exposed to the material to be compressed. This area is generally between the jaw edge 106 of a particular jaw 94 and a line or point projected on that jaw 94 by the plane of the compression surface 102 of an adjacent jaw 94, or that is contacted by or adjacent to the jaw edge 106 of an adjacent jaw 94. For example, in a press device 50 with eight jaws 94 cooperate to form a generally octagonal compression cavity. One side of that octagon defines the area of a compression surface 102 exposed to the material to be compressed. As the jaws 94 move inwardly, the octagon shrinks, and the area of each side and therefore each compression surface 102 decreases. The compression surfaces 102 define a hypothetical cylinder 110 that is, in a radial direction, a hypothetical circle of maximum diameter that can be inscribed within the compression surfaces 102. In the example described in this paragraph, the circle is a circle of maximum diameter that is inscribed within the octagon defined by the compression surfaces 102. As a result, as the jaws 94 move inwardly, the hypothetical cylinder 110 also shrinks in diameter.

The attachment of the jaw 94 to the tool carrier 98 can include a biasing mechanism 100 configured to urge the jaw 94 in a direction away from the pivot pin 66 and toward a clockwise-adjacent jaw 94. In other words, the biasing mechanism 100 pushes the jaw 94 toward a clockwise-adjacent jaw 94, whereas such clockwise-adjacent jaw 94 resists such pushing. In this manner, any gap that would otherwise exist between adjacent jaws 94 will be closed by the contact between adjacent jaws 94.

The biasing mechanism 100 can be any suitable mechanism, component, force, or combination of these capable of biasing a jaw 94 toward an adjacent jaw 94. The biasing mechanism 100 can be disposed on one or more of a lever 54, jaw 94, and any other element of the press device 50. The biasing mechanism 100 can be disposed between a lever 54 and a jaw 94, particularly on, in, or in the vicinity of a tool carrier 98. Suitable biasing mechanisms 100 include, but are not limited to, bevel, tension, and compression springs; pneumatic and/or hydraulic components including cylinders or bladders; elastomeric components such as an elastomeric block or an elastomeric band; mechanical gearing such as a rack and pinion or non-circular gearing; a cam mechanism including followers or a contoured wedge mechanism; electrical components including a solenoid; magnetic forces; vacuum; mechanical engagement such as a t-slot pin-type mechanism; a supplemental linkage connected between two or more jaws 94, and any combination of these. The biasing mechanism 100 can be disposed directly on or near the jaws 94, or can be external components that direct influence to the jaws 94.

Activating the drive mechanism and rotating the chain link 82 causes the lever 54 to pivot about the pivot pin 66. The lever 54 pivots such that the radially-inward end portion 90 of the lever arm 86 moves radially inward when the chain link 82 is rotated in a clockwise direction in this example. Each compression surface 102 moves radially inwardly with the end portion 90 to which it is attached. Thus, the press device 50 closes when the chain link 82 is rotated in a clockwise direction in this example, and the press device 50 opens when the chain link 82 is rotated in a counterclockwise direction in this example. It can be seen that the jaws 94, and particularly a point on a jaw 94, can be configured to move in a nonlinear manner, or in a curvilinear manner depending on the arrangement of levers, pins, fixed rings, and chain links.

In many prior presses, linear or quasi-linear travel of the jaws in a radial direction leaves a gap between jaws in which portions of the uncompressed material can be trapped. In some cases where a multi-lobed tampon is desired, such intrusion of uncompressed material into a gap is intentional. Other prior presses seek to address the gap issue by installing a second set of jaws in the gaps between the first set of jaws. This second set of jaws is intended to at least partially fill the gaps to address the portion of uncompressed material intruding in the gaps. The two sets of jaws leads to a complicated arrangement of jaws and levers.

In addition, many prior presses, jaws can interfere with and impinge upon adjacent jaws at small compressions (i.e., when the jaws near their inward extent of travel). In contrast, the press device 50 of the present disclosure can theoretically move inwardly until the jaw edge 106 of each jaw 94 meets the others at the central longitudinal axis 58 of the press device 50. In other words, the jaws 94 can move inwardly until the hypothetical cylinder 110 defined by the compression surfaces 102 reaches a diameter of zero.

FIG. 2 illustrates that in the open starting position the jaw edges 106 of the jaws 94 are not directed toward the central longitudinal axis 58 of the press device 50 but tangentially toward a hypothetical cylinder 110 that surrounds the central longitudinal axis 58 at a selected distance. Thus it is achieved that the compression forces that are applied by the jaws 94 are not centrally but tangentially directed toward a circle that surrounds the material to be manufactured at a selected distance.

In the open starting position of the device 50 according to FIG. 2, a blank 114 of material is inserted into the opening between the compression surfaces 102. This blank 114 in one aspect is manufactured by winding up an absorbent material section. By rotating the chain links 82 clockwise relative to the fixed ring 62, the compression surfaces 102 are first brought into an intermediate position and finally into the end position illustrated in FIG. 3. With this pivoting movement, the levers 54 are pivoted about the pivot pins 66. A comparison of FIG. 3 with FIG. 2 shows that during this movement the deformation forces that are applied by the compression surfaces 102 lead to a volume reduction of the blank 114 that is uniform about the periphery and transform the blank 114 into a compressed blank 114 (or a pledget 20 in the case of a tampon 10). After slightly opening the jaws 94, the compressed blank 114 is removed from the device 50.

Prior presses incorporate multiple compression jaws that cooperate with each other such that the clearance between adjacent jaws forms a gap. Each gap defines a gap centerline. Lines including the gap centerlines of prior presses generally pass through or near the center of such presses. This arrangement in prior presses allows material to intrude into the gap. In the press device 50 of the present disclosure, the elimination of gaps helps prevent intrusion of material into a gap.

In various aspects of the present disclosure, the substantially reduced clearance between adjacent jaws 94 approaches zero such that there is no practical gap present throughout the compression cycle, such that migration of material around the contacting surfaces is substantially limited.

Prior devices tend to teach the need for a highly complex devices where the die cavity is operative only by the incorporation of a number of members including stationary members, spring-loaded members, and multiple forming fingers. These devices also can require an outer ring in combination with a cam mechanism, motor, and oscillating gear box to drive the members back and forth to compress and open a cavity.

The present disclosure advantageously provides a simple one jaw (finger) member 94 that is mounted to a movable lever 54 that rotates or pivots about a pivot pin 66 to move each jaw 94 in an arcuate motion to create a generally continuous compression cavity. The press device 50 does not require a ball bearing or roller bearing as in prior devices. Instead a simple bearing surface is all that is needed. There is also no need in the present disclosure for a stationary member to form a portion of the compression cavity described.

Prior devices require at least two different members to form a compression cavity, whereas the present disclosure advantageously teaches that only one member is necessary. Prior devices also require a complex mechanism with various linkages to open and close the press. The present disclosure advantageously provides a single set, in one example, of eight jaws 94 with their corresponding levers 54 to form the compression cavity.

The present disclosure recognizes that, although a continuous compression cavity is one means to accomplish uniform compression, uniform compression can also be accomplished with a tangential space present between adjacent jaws 94, because the compression surface 102 also creates uniform pressure, as in the present disclosure. Although the tangential space in one aspect of the present disclosure has a discrete step at the interface where one jaw 94 overlaps an adjacent jaw 94, the surface segments that create pressure are continuous throughout the compression cavity when viewed from a perspective view in the radial direction.

It should be noted that prior devices do not teach or recognize any adverse consequences to having spaces between adjacent jaws due to the general radial orientation of the compression jaws.

A further advantage of the present disclosure over existing presses is that complexity, cost, maintainability, press open dimensional range, and flexibility of the press device 50 are greatly simplified such that now each jaw 94 functions as a compression surface 102 and forms a segment of the compression cavity. This advantageously allows each jaw 94 to be optimized for various features because of the inter-changeability of jaws 94. The prior art shows that a holder and/or a stationary surface in combination with the jaw (finger) 94 is required to form at least a portion of the compression cavity. At minimum compression, adjacent jaws 94 of the present disclosure also advantageously cooperate with each other to provide additional resistance to the high pressures created at the surface of the adjacent jaw 94 that is in front of it.

An additional advantage of the present disclosure is the ability of the arrangement described to be used in conjunction with standard and existing tampon or other machinery. This results in minimized equipment development time and costs.

The absorbent blanks 114 and ultimately the pledgets 20 of the present disclosure can include any suitable type and/or combination of absorbent fibers and/or binder fibers. The absorbent fibers can include any suitable absorbent material made from artificial or natural fibers, such as polyester, cellulose, acetate, nylon, polypropylene, rayon, cotton or blends thereof. The absorbent fibers can also include any suitable blend of fibers. For example, the absorbent fibers can be formed from cellulosic fibers, such as cotton and rayon. The absorbent fibers can be 100 wt % cotton, 100 wt % rayon, or a blend of cotton and rayon fibers. In some aspects, the cellulose fibers can be modified for super-absorbency.

In some aspects, the absorbent blanks 114 and ultimately the pledgets 20 can include a combination of absorbent fibers and long binder fibers like those taught in U.S. patent application Ser. No. 13/051,447 to Jackson et al. that was filed on Mar. 18, 2011, and is incorporated herein by reference where not contradictory hereto.

When cotton fibers are used, the cotton fibers should have a staple length of between about 20 millimeters (mm) to about 40 mm. The cotton fibers should generally have a fiber size of between about 15 microns to about 28 microns. The cotton fibers can also be bleached if desired. Bleaching will make the cotton fibers whiter in appearance.

When rayon fibers are present, the rayon fibers should have a staple length of between about 20 mm to about 45 mm. In some aspects, rayon fibers can have a staple length of 38-42 mm. Suitable rayon fibers can have a denier of between about 1 to about 6. In specific aspects, the rayon fibers can be viscose rayon, lyocell rayon, or any other suitable rayon or regenerated cellulose.

The rayon fibers can have a circular, bi-lobal, or tri-lobal cross-sectional configuration, or some other cross-sectional configuration known to those skilled in the art. The bi-lobal configuration has a cross-sectional profile that looks like a dog bone while the tri-lobal configuration has a cross-sectional profile that looks like a “Y”. The rayon fibers can also be bleached if desired.

In various aspects, the absorbent blanks 114 can be rolled, stacked, folded, or otherwise manipulated before being compressed into pledgets 20. For example, suitable menstrual tampons can include “cup” shaped pledgets like those disclosed in U.S. Patent Application Publication 2008/0287902 to Edgett and U.S. Pat. No. 2,330,257 to Bailey; “accordion” or “W-folded” pledgets like those disclosed in U.S. Pat. No. 6,837,882 to Agyapong; “radially wound” pledgets like those disclosed in U.S. Pat. No. 6,310,269 to Friese; “sausage” type or “wad” type pledgets like those disclosed in U.S. Pat. No. 2,464,310 to Harwood; “M-folded” tampon pledgets like those disclosed in U.S. Pat. No. 6,039,716 to Jessup; “stacked” tampon pledgets like those disclosed in U.S. Patent Application Publication 2008/0132868 to Jorgensen; or “bag” type tampon pledgets like those disclosed in U.S. Pat. No. 3,815,601 to Schaefer.

A suitable method for making “radial wound” pledgets is disclosed in U.S. Pat. No. 4,816,100 to Friese. Suitable methods for making “W-folded” pledgets are disclosed in U.S. Pat. No. 6,740,070 to Agyapong; U.S. Pat. No. 7,677,189 to Kondo; and U.S. Patent Application Publication 2010/0114054 to Mueller. A suitable method for making “cup” pledgets and “stacked” pledgets is disclosed in U.S. Patent Application Publication 2008/0132868 to Jorgensen.

In various aspects, the tampons 10 of the present disclosure can also include a cover material disposed over at least a portion of the outer surface. The cover can be beneficial in assuring that the fibers of the pledget 20 do not directly contact the inner walls of a woman's vagina. This minimizes the likelihood that fibers will be left behind in the vagina after the tampon 10 has been removed. The cover can be tucked into the insertion end 38 and/or the withdrawal end 42 so as to substantially or completely surround and enclose the absorbent fibers. The cover can also be constructed from a heat-sealable material to assist in bonding all or portions of it to the pledget 20, such as by heat and/or pressure.

The optional cover can be formed from a nonwoven material such as a polyolefin, particularly polypropylene or polyethylene. The cover material can be spunbond. In some aspects, the cover material can be a bonded carded web made of bicomponent fibers (e.g., polyethylene/polyethylene terephthalate sheath core). In some aspects, the cover material can be a film material made from polypropylene, polyethylene, or a combination of both. For example, in some aspects, the cover can have three layers made of polyethylene-polypropylene-polyethylene. In some aspects, the cover material can have apertures having a diameter of 1 mm or less or 0.5 mm or less.

In various aspects, the withdrawal string 21 can be attached to the pledget 20 in any suitable manner. For example, an opening can be formed through the pledget 20 (and cover if provided) so as to provide a means for attaching a withdrawal string 21. In various aspects, the withdrawal string 21 can be attached to the absorbent blank 114 before or after it is compressed into the pledget 20. The withdrawal string 21 can be attached to the pledget 20 and then looped upon itself. A knot 31 can then be formed near the free ends of the withdrawal string 21 to assure that the string 21 does not separate from the pledget 20. The knot 31 also serves to prevent fraying of the withdrawal string 21 and to provide a place or point where a woman can grasp the withdrawal string 21 when she is ready to remove the tampon 10 from her vagina.

The withdrawal string 21 can be constructed from various types of threads or ribbons. A thread or ribbon can be made from 100 percent cotton fibers and/or other materials in whole or part. In some aspects, the withdrawal string 21 can be 67% polyethylene terephthalate and 33% rayon. The withdrawal string 21 can be bonded to the absorbent blank 114 and/or the pledget 20 with or without tying. The withdrawal string 21 can have any suitable length and/or the withdrawal string 21 can be dyed and/or treated with an anti-wicking agent, such as wax, before being secured to the pledget 20.

While the disclosure has been described in detail with respect to specific aspects thereof, it will be appreciated that those skilled in the art, upon attaining understanding of the foregoing will readily appreciate alterations to, variations of, and equivalents to these aspects. Accordingly, the scope of the present disclosure should be assessed as that of the appended claims and any equivalents thereto. Additionally, all combinations and/or sub-combinations of the disclosed aspects, ranges, examples, and alternatives are also contemplated. 

The invention claimed is:
 1. An apparatus for compressing a material, the apparatus comprising: a plurality of levers, each lever comprising a lever outer end and a radially-inward end portion and a lever longitudinal axis extending from the lever outer end to the radially-inward end portion; a plurality of jaws each attached to a lever to form a lever/jaw combination, wherein each jaw has a compression surface having an area and wherein the compression surface defines a plane that is generally parallel to the lever longitudinal axis; a compressing mechanism configured to move each lever in a non-linear motion such that the area of a compression surface exposed to the material decreases with the inward movement of that compression surface, wherein each lever/jaw combination includes a biasing mechanism configured such that adjacent jaws contact each other.
 2. The apparatus of claim 1, wherein the biasing mechanism is configured such that adjacent jaws contact each other throughout a compression cycle.
 3. The apparatus of claim 1, wherein the motion of each jaw is curvilinear.
 4. The apparatus of claim 1, wherein the material has an initial compression diameter and a final compression diameter, and wherein the ratio of the initial compression diameter to the final compression diameter obtainable with the apparatus is greater than two.
 5. The apparatus of claim 1, wherein the material has an initial compression diameter and a final compression diameter, and wherein the ratio of the initial compression diameter to the final compression diameter obtainable with the apparatus is greater than five.
 6. The apparatus of claim 1, wherein the material has an initial compression diameter and a final compression diameter, and wherein the ratio of the initial compression diameter to the final compression diameter obtainable with the apparatus is greater than ten.
 7. The apparatus of claim 1, wherein the material has an initial compression diameter and a final compression diameter, and wherein the ratio of the initial compression diameter to the final compression diameter obtainable with the apparatus is greater than twenty.
 8. The apparatus of claim 1, further comprising a fixed ring, wherein each lever is pivotably attached to the fixed ring with a pivot pin, wherein adjacent levers are pivotably connected to a chain link, and wherein the pivot pin is disposed between the jaw and the chain link.
 9. The apparatus of claim 1, wherein each lever includes a lever longitudinal axis, wherein each lever is fixed longitudinally, and wherein each jaw is movable longitudinally with respect to its lever.
 10. The apparatus of claim 1, wherein the biasing mechanism includes a spring or an elastomeric component.
 11. The apparatus of claim 1, wherein the biasing mechanism includes a pneumatic component, a hydraulic component, or an electrical component.
 12. The apparatus of claim 1, wherein the biasing mechanism includes mechanical gearing or a cam mechanism.
 13. The apparatus of claim 1, wherein the biasing mechanism includes a mechanical engagement mechanism or a supplemental linkage.
 14. An apparatus for compressing a material, the apparatus having a central longitudinal axis and comprising: a plurality of levers, each lever comprising a lever outer end and a radially-inward end portion and a lever longitudinal axis extending from the lever outer end to the radially-inward end portion and each lever having a tool carrier; a plurality of jaws each attached to a lever at a tool carrier to form a lever/jaw combination, wherein each jaw has a compression surface having an area and wherein the compression surface defines a plane that is generally parallel to the lever longitudinal axis; a compressing mechanism configured to move each lever in a non-linear motion such that the area of a compression surface exposed to the material decreases with the inward movement of that compression surface, wherein each lever/jaw combination includes a biasing mechanism configured such that adjacent jaws contact each other, and wherein the plane of each compression surface is predominantly tangential to the apparatus central longitudinal axis.
 15. The apparatus of claim 14, wherein each lever includes a lever longitudinal axis, wherein each lever is fixed longitudinally, and wherein each jaw is movable longitudinally with respect to its lever.
 16. The apparatus of claim 14, wherein the biasing mechanism includes one or more of a spring, an elastomeric component, a pneumatic or hydraulic component, an electrical component, mechanical gearing, a cam mechanism, a mechanical engagement mechanism, and a supplemental linkage.
 17. An apparatus for compressing a material, the apparatus comprising: a plurality of levers, each lever comprising a lever outer end and a radially-inward end portion and a lever longitudinal axis extending from the lever outer end to the radially-inward end portion and each lever having a tool carrier; a plurality of jaws each attached to a lever at a tool carrier to form a lever/jaw combination, wherein each jaw has a compression surface having an area and wherein the compression surface defines a plane that is generally parallel to the lever longitudinal axis; a compressing mechanism configured to move each lever in a non-linear motion such that the area of a compression surface exposed to the material decreases with the inward movement of that compression surface, wherein each lever/jaw combination includes a biasing mechanism configured to bias its jaw along the lever longitudinal axis toward an adjacent jaw.
 18. The apparatus of claim 17, wherein each lever is fixed longitudinally, and wherein each jaw is movable longitudinally with respect to its lever.
 19. The apparatus of claim 17, wherein the biasing mechanism includes one or more of a spring, an elastomeric component, a pneumatic or hydraulic component, an electrical component, mechanical gearing, a cam mechanism, a mechanical engagement mechanism, and a supplemental linkage. 